what is the properties of light, light is a form of energy, light travels very slow, light can't travel in a straight line, moon is a luminous object, true, false, what is this, sun, moon, cotton, candle, is it a luminous or non luminous object, luminous, non luminous, natural light, moon, sun, bulb, tube light.

light

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列印
嵌入

排行榜

視覺風格

選項

切換範本

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